In the field large lattice boom cranes operate that are assembled on site in order to be used. Often the main boom and/or the back mast of the crane are assembled whilst lying on the ground. A quite common problem is that limited space is available at the site to build up the crane, e.g. when a new reactor vessel is to be installed at an existing petrochemical plant.
NL1040507 proposes to build up the crane on site from individual parts, which have a length that allows them to be transported by road and/or sea in regular ISO freight containers, e.g. having 20 or 40 ft. length. The individual parts are releasably connected to each other to form for example a ballast mast, a back mast and a main boom. These completed main components of the crane are then connected to each other, and then they are tilted upwards to complete the crane. In practice, even this known crane still requires quite some spaces one site, because the masts and main boom have to be assembled on the ground to their full length.
A further issue related to existing cranes is that they often have to operate on sites where existing buildings and/or equipment is present and needs to be avoided. So, there is often little room to arrange the crane and operate it in a safe and adequate manner.
The above issues are in particular of relevance for very large cranes, e.g. having a length of back mast and/or main boom of over 100 meters, so without counting any fly jib.